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There is a strong inducement to develop new inorganic materials to substitute the current industrial pigments, which are known for their poor ultraviolet absorbent and low photoluminescence (PL) properties. The purpose of this paper is to invent a better rare-earth-based pigment material as a spectral modifier with good luminescence properties to enhance the spectral response for photovoltaic panel application.

Different phosphor samples made of nano-calcium carbonate (CaCO₃) with varied wt.% of the dopant Dysprosium doped calcium borophosphate (CBP/Dy) as (W0 – 0%, W1 – 3,85%, W2 – 7.41%, W3 –10.71% and W4 –13.79%) were prepared via the solid-state diffusion method at 600 °C for 6 h using a muffle furnace. The structural, morphological and luminescence properties of the CaCO₃:CBP/Dy powder samples were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and PL test.

The XRD, SEM and FTIR results verified the crystalline formation, morphological behaviour and vibration bonds of synthesized CBP/Dy-doped CaCO₃ powder samples. XRD pattern revealed that the synthesized powder samples exhibit crystalline structured materials, and SEM results showed irregular shape and porous-like structured morphologies. FTIR spectrum shows prominent bands at 712, 874 and 1,404 cm⁻¹, corresponding to asymmetric stretching vibrations of CO3²⁻ groups and out-of-plane bending. PL characterization of CBP/Dy-doped CaCO₃ (sample W) shows emission at 427 nm (λmax) under the excitation of 358 nm. The intensity of PL emission spectra drops due to the concentration quenching effect, while the maximum PL intensity is observed in the W3 phosphor powder system.

This phosphor powder is expected to find out the potential application such as a spectral modifier which is applied to match the energy of photons with solar cell bandgap to improve spectral absorption and lead to better efficiency.

The introduction of a nano-CaCO₃:CBP/Dy hybrid powder system with good luminescence properties to be used as spectral modifiers for solar cell application has been synthesized in the lab, which is a novel attempt.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

This study aims to fabricate the acrylic-based polymeric composite coating with a hydrophobic surface associated with natural oil polyol (NOP) and polydimethylsiloxane with the incorporation of 3 Wt.% SiO₂ nanoparticle (SiO₂np) against the corrosive NaCl media.

The structural properties of the formulated polymeric composite coatings were investigated by using Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, water contact angle (WCA) and cross-hatch (X-Hatch) tests. The WCA measurement was used to study the surface wettability of the formulated polymeric composite coatings. The corrosion protection performance of the nanocomposite coated on the mild steel substrate was studied by immersing the samples in 3.5 Wt.% NaCl solution for 30 days using electrochemical impedance spectroscopy.

The enhanced polymeric composite coating system performed with an excellent increase in the WCA up to 111.1° which is good hydrophobic nature and very high coating resistance in the range of 10¹⁰ Ω attributed to the superiority of SiO₂np.

The incorporation of SiO₂np into the polymeric coating could enhance the surface roughness and hydrophobic properties that could increase corrosion protection. This approach is a novel attempt of using NOP along with the addition of SiO₂np.

The purpose of this study is to develop anti-corrosion coating systems using disposable waste materials. The dissolved polyethylene terephthalate (PET) has been blended with epoxy resin and stoichiometrically cured with a polyamide resin.

Glycolysis process was found to be the most optimum candidate to dissolve PET. The developed coating systems were characterized by Fourier transform infrared spectroscopy for confirmation of the molecular bonding structures. The mechanical properties were characterized by performing pull-off test and cross hatch test for mechanical properties on the coated panel. Also, the glossiness test was used by reflecting light on the coated surface. The corrosion protection performance of the coated mild steel panels was examined using electrochemical impedance spectroscopy. Furthermore, the wettability of the developed coating systems was evaluated by using water contact angle technique.

It was observed that the coating system which contains 10 per cent of dissolved PET (S2) showed the highest adhesion and corrosion protection properties.

Recyclable PET bottles have outstanding chemical properties, adhesion properties, low cost, low permeability to gases and solvents making it suitable as a coating with superior barrier properties.

The purpose of this paper is to develop the bio-composite organic coatings by adding the bio-based additives that are extracted from banana peels and henna leaves as the organic corrosion inhibitors.

Bioactive constituents with inhibition properties are extracted from banana peels and henna leaves by using ethanol to form the ethanolic extract. The inhibiting efficiency of these bioactive constituents on mild steel corrosion in 3.5% sodium hydroxide (NaCl) solution is investigated. The investigation is performed using electrochemical impedance studies for 30 days. The optical and adhesive properties of the bio-composite coating systems have also been studied.

The best protection is obtained as the loading ratio of the banana peels ethanolic extract (BPEE) and henna leaves ethanolic extract (HLEE) are 10 Wt.% and 30 Wt.%, respectively. Overall, the results obtained show that the BPEE and HLEE not only enhance the optical properties but also can serve as an effective inhibitor for corrosion without affecting the adhesiveness of the neat acrylic properties.

Banana peels and henna leaves consist of bioactive constituents that have anti-corrosion properties which could inhibit corrosion.

The purpose of this paper is to implement coating system by varying the amount of nano-sized titanium dioxide, (nano-TiO₂) combined with various organic binders and to study the coating effects on the performance of solar cell in terms of temperature and efficiency.

Nano-TiO₂ coatings are developed in two types of binder networks; the combination of methyltrimethoxy silane (MTMS) and nitric acid and the combination of 3-aminopropyl triethoxysilane (APTES) and MTMS. Overall, the formulations method was cost-effective, produces good transparency, clear and managed to dry at room temperature. The coating mixtures were applied onto the glass substrate by using the dip-coating method and the coated substrate were sent for several characterizations.

This study demonstrated that TiO₂ nanoparticle coating in APTES/MTMS matrix showed a thermal-decreasing result on solar cells, where the cell temperature is reduced to 46.81°C (T₂ coating type) from 55.74°C (without coating) after 1-h exposure under 1,000 W/m² irradiance in a solar simulator. Contrary to prior works where solar cell coatings were reported to reduce the cell temperature at the expense of the cell efficiency, the results from this study reported an improved fill factor (FF) of solar cells. From the photovoltaic (PV) characteristics study, the FF for solar cells is increased by approximately 0.2, i.e. 33.3 per cent, for all coatings compared to the non-coated cell.

Findings will be able to contribute in the development of temperature-reducing and efficiency-enhancing coating for PV panels.

A simple dip-coating method provides an even distribution of TiO₂ nanoparticle coating on the glass panel, which is cost-effective and time-efficient to reduce the temperature of solar cell while maintaining its efficiency.

The ability of nano-TiO₂ coatings with a simple fabrication method and the right solution to reduce the surface temperature of solar cells while improving the FF of the cells.

This paper aims to study the corrosion performance and physical properties of hybrid paint systems based on zinc-rich primer (ZRP) and to determine the optimum modification approach that guarantees the most overall performance enhancement for the developed coating films that have been fabricated based on the usage of ZRP.

Four different approaches were applied to enhance the corrosion protection performance and the physical properties of ZRP-based paint systems, namely, incorporation with TiO₂ pigment, introducing SiO₂ nanoparticles, usage of polyamide curing agent and application of epoxy base coating as a second layer. The physico-mechanical properties were examined using pull-off test, glossiness test, pencil hardness test and cross-cut adhesion tape test. Moreover, the contact angle measurement was used to study the wettability of the developed coated surfaces and the corrosion protection performances were evaluated by using electrochemical impedance spectroscopy and salt spray test.

The obtained results revealed the ability of a certain approach to enhance the physical and corrosion protection properties of the ZRP paint system. Moreover, developing an intact hydrophobic nanocomposite paint system based on the usage of ZRP as the host matrix and SiO₂ nanoparticles as the reinforcing agent was confirmed without altering the cathodic protection mechanism or the other desired characteristics of ZRP paint system.

The innovation of this work can be clearly observed by the ability to enhance the physical and corrosion protection properties of ZRP with four different approaches.

This study aims to propose that the corrosion resistance of the neat epoxy coating can be further enhanced by incorporating reinforcing agents.

Chitosan, silica and their hybrid compound were used to study the subject of corrosion resistance of epoxy coating systems. This work used 3.5 Wt.% NaCl solution as the electrolyte, and electrochemical impedance spectroscopy (EIS) was used to investigate the electrochemical behaviour of the studied coating systems. Standard and accelerated states were used without and with scratch on the coating layer.

It was found that the impedance value of composite coating incorporated with the hybrid compound was significantly higher at 10¹⁰ Ω after 14 days of exposure in both testing states. The breakpoint frequency (f_b) determination also proves with large capacitive region at low-to-high frequency of impedance plots corresponding to the high corrosion resistance.

The hybrid compound consisting of chitosan as organic biopolymer and silica as inorganic material, respectively, served as a promising reinforcing agent for composite coating as a promising corrosion inhibitor. Different states of EIS measurement were used which are standard (without scratch) and accelerated (with scratch) states associated with the f_b values.

The purpose of this paper is to develop different combinations of acrylic polyol and silicone resins with various weight ratios and to test the coating properties using electrochemical impedance spectroscopy (EIS).

The performance properties such as coating resistance, capacitance, dielectric constant, water uptake and diffusion coefficient were evaluated using EIS with exposure to 3.5 per cent NaCl solution for 60 days.

The binders developed in this study were coated on cold rolled steel plates. The dry film thickness was found to be in the range of 50 microns. From EIS results, it was found that Acrylic polyol sample with 30 weight per cent of silicone exhibits the best properties, as it has high coating resistance in the range of 109 Ohms for the full period of exposure, whereas all other samples showed poor performance with the exposure time. For these samples, the parameters measured such as the coating resistance of the samples decreased while the coating capacitance, percentage of water uptake and diffusion coefficient of the samples increased after being exposed to corrosive solution for 60 days. The coatings developed by 0, 10 and 60 weight per cent silicone showed high coating capacitance on the first day of exposure, and these systems failed early during the exposure. The water uptake percentage and diffusion coefficient of all samples were found to be less than 50 per cent and below 10-11 cm2 s−1, respectively. An optimum cross-linking between the resins is considered as the main contribution for the best performance shown by the sample that consists of 30 weight per cent of silicone in acrylic matrix that provides maximum barrier properties of the coating.

Developing coatings using hybrid binders (silicone resin and acrylic polyol resin) is new area of research. This will explore more research in the formulation of novel coatings.

States that there is compelling evidence that the Japanese retail distribution system is changing. This study uses census data for ten years (1985 to 1994) to understand past changes in the structure of the retail distribution system. To understand the likely changes to the distribution system in the future, data were collected from 136 Japanese manufacturers and retailers. Results suggest significant future changes in the number of retailers, specialty stores, general merchandise stores, discount stores, and non‐store retailing.